Ok, so Derek made his decision, now Mer has chosen him. What if he doesn't want her to and still walks away?? hmmmm.... can't wait for Thurs!

Of course she chose him - she is in love with him. The vet was just a very very nice diversion. But, I think she at least should have made Derek sweat a whole lot more for what he did to her. If he hurts her again, he's a cad and she's a fool (but then who isn't when it comes to love).

I KNEW that Mer would choose Mc.Dreamy...who'd ever doubt that?!?
In fact, I would have probably chosen him too! Women (usually) never think with their heads, their heart always gets in the way of their decision making.